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Today's Topics:
1. Re: Generating Random Float (MAN)
----------------------------------------------------------------------
Message: 1
Date: Fri, 23 Apr 2010 12:23:14 -0300
From: MAN <[email protected]>
Subject: Re: [Haskell-beginners] Generating Random Float
To: Giorgio Stefanoni <[email protected]>
Cc: [email protected]
Message-ID: <1272036194.2345.1.ca...@dy-book>
Content-Type: text/plain; charset="UTF-8"
Works great here...
Using ghci:
Prelude> :m + Random
Prelude Random> let rand :: (Num a,Random a) => IO a; rand = newStdGen
>>= return . fst . randomR (0,1)
Prelude Random> rand :: IO Int
1
Prelude Random> rand :: IO Int
1
Prelude Random> rand :: IO Int
1
Prelude Random> rand :: IO Int
1
Prelude Random> rand :: IO Int
0
Prelude Random> rand :: IO Double
0.6897753065428174
Prelude Random> rand :: IO Float
0.6159074
Prelude Random>
El vie, 23-04-2010 a las 15:33 +0200, Giorgio Stefanoni escribió:
> Hi guys,
>
> I'm working with Haskell for a little project at the university and
> I'm stuck with a problem.
>
> I'm trying to generate a random number in the interval [0.0,1.0]. It
> is straightforward for me to implement the function on ints:
>
> rand :: IO Int
> rand = do r <- newStdGen
> let (x1, r2) = randomR (0,1) r
>
> print x1
> return x1
>
>
> However, if I try to generate a Float instead, I always get an
> Arithmetic Overflow error that I can not understand.
>
> Code:
> rand :: IO Float
> rand = do r <- newStdGen
> let (x1, r2) = randomR (0.0::Float,1.0::Float) r
>
> print x1
> return x1
>
>
> Do you have any clue why this happens?
>
> Thanks in advance,
>
>
> --
> Giorgio
> _______________________________________________
> Beginners mailing list
> [email protected]
> http://www.haskell.org/mailman/listinfo/beginners
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